How can we print weights per iteration in a simple feed forward MLP for an specific class?
A common model used for this kind of classification task is to have one output neuron per class. So, for example, neuron 1 may have a loss function that is related to outputting "1" for examples of class 1, and "0" for examples of other classes. Neuron 2 may be asked to do the same, but for class 2 rather than class 1.

If you use a model of this kind, you can pull the weights for each neuron in the final output layer. It sounds like this is what you are being asked to plot.